STUDY OF FERROMANGANESESILICON METAL FORMATION FROM COMPOSITE BRIQUETTEMANGANESE ORE AT 1450OC-1550OC

• Main Author: Ayu Ramadhanti, Fauzia
• Format: Final Project
• Language: Indonesia
• Subjects: Karya Umum
• Online Access: https://digilib.itb.ac.id/gdl/view/40234
• Institution: Institut Teknologi Bandung

Ferromanganese and siliconmanganese act as deoxidizer, desulfurizing agent, and alloy components to improve mechanical properties in steel. These alloys have an opportunity to be developed in Indonesia because of the availability of manganese ore resources in Indonesia, and increasing of steel needs. However, this alloy production in Indonesia is very low. As an effort to utilize manganese resources, research on manganese ore processing was carried out to produce ferromanganesesilicon metal. This research studied effect of coal addition in composite briquettes and final isothermal temperature on ferromanganesesilicon metal recovery, iron, manganese and silicon content, and slag appearance as a result of reduction by isothermal-gradient temperature method. A series of experiments were performed with variations in the addition of coal, and final isothermal temperatur. Initial characterization of ore was carried out by X-Ray Diffraction (XRD) and X-Ray Fluorosence (XRF), while coal characterization was done by proximate test, ultimate test and ash content test. Two gram manganese ore was formed into composite briquettes with variations in the addition of coal 5%, 10%, 15%, 20%, 25%. Furthermore, the composite briquette reduction process was carried out by isothermal-gradient temperature method starting with isothermal heating at 1000° C for 30 minutes, then temperature was increased to 1450oC, 1500oC, and 1550oC with temperature gradient of 10oC/minutes. In the last stage the heating was carried out isothermally with total time of reduction 140 minutes. The result of reduction wereferromanganesesilicon metal, and slag in liquid phase. The metalweight and diameter were recorded. In addition, the reduction products were also analyzed by optical microscope, Electron Probe Microanalyzer-Wavelength Dispersive Sprectroscopy (EPMA-WDS), Scanning Electron Microscope-Energy Dispersive Spectrometer (SEM-EDS), ImageJ and XRD for slag. The results showed that the addition of coal to the briquettes and final isothermal temperature could increase the recovery of metal, and the color of the slag was getting greener. This can be observed from the decreasing content of manganese in slag, and the increase in the recovery of iron and silicon. The highest recovery of ferromangansilicon metal was obtained by adding 20% coal at a temperature of 1500oC, which is 22.71% with a large number of small metal particles. The metal produced at 1450°C is close to the specifications of ferromanganese metal with iron content of 4.97%, manganese content of 92.82%, and silicon content of 2.22%. The metal produced at 1550° C is close to the specifications of siliconmanganese metal with an iron content of 8.82%, manganese content of 73.54%, and silicon content of 17.63%.